I've been saying from the beginning that this needs to happen since they chose to do DOFP. There needs to be a meaningful team in the past for the future traveler to meet, and not a bunch of stranger X-students.

And meeting the younger version of Professor X, Magneto, Mystique and Beast isn't enough?

It would be nice to see Wolverine/Storm/Rogue/Iceman/Shadowcat meet the 70s (or the ideal 80s) X-Men team that consist of young Cyclops/young Jean/young Storm/young Prof X. But its not like they are going to the 70s and the team just consists of Havok, Polaris, Banshee and Dazzler. Professor X and Beast are still in the team and they will probably meet the younger version of Mystique and Magneto when they face the Brotherhood.